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International audience; BACKGROUND: EZH2 is overexpressed and associated with poor prognosis in adrenocortical carcinoma (ACC) and its inhibition reduces growth and aggressiveness of ACC cells in culture. Although EZH2 was identified as the methyltransferase that deposits the repressive H3K27me3 histone mark, it can cooperate with transcription factors to stimulate gene transcription. METHODS: We used bioinformatics approaches on gene expression data from three cohorts of patients and a mouse model of EZH2 ablation, to identify targets and mode of action of EZH2 in ACC. This was followed by ChIP and functional assays to evaluate contribution of identified targets to ACC pathogenesis. RESULTS: We show that EZH2 mostly works as a transcriptional inducer in ACC, through cooperation with the transcription factor E2F1 and identify three positive targets involved in cell cycle regulation and mitosis i.e., RRM2, PTTG1 and ASE1/PRC1. Overexpression of these genes is associated with poor prognosis, suggesting a potential role in acquisition of aggressive ACC features. Pharmacological and siRNA-mediated inhibition of RRM2 blocks cell proliferation, induces apoptosis and inhibits cell migration, suggesting that it may be an interesting target in ACC. CONCLUSIONS: Altogether, these data show an unexpected role of EZH2 and E2F1 in stimulating expression of genes associated with ACC aggressiveness. British Journal of Cancer https://doi.org/10.1038/s41416-019-0538-y BACKGROUND Adrenocortical carcinomas (ACC) are endocrine malignancies associated with dismal prognosis. At diagnosis, 80% of patients present metastases reducing the 5 years survival rate below 30% for most series.

International audience; In mouse embryonic stem cells (mESCs), chemical blockade of Gsk3α/β and Mek1/2 (2i) instructs a self-renewing ground state whose endogenous inducers are unknown. Here we show that the axon guidance cue Netrin-1 promotes naive pluripotency by triggering profound signalling, transcriptomic and epigenetic changes in mESCs. Furthermore, we demonstrate that Netrin-1 can substitute for blockade of Gsk3α/β and Mek1/2 to sustain self-renewal of mESCs in combination with leukaemia inhibitory factor and regulates the formation of the mouse pluripotent blastocyst. Mechanistically, we reveal how Netrin-1 and the balance of its receptors Neo1 and Unc5B co-regulate Wnt and MAPK pathways in both mouse and human ESCs. Netrin-1 induces Fak kinase to inactivate Gsk3α/β and stabilize β-catenin while increasing the phosphatase activity of a Ppp2r2c-containing Pp2a complex to reduce Erk1/2 activity. Collectively, this work identifies Netrin-1 as a regulator of pluripotency and reveals that it mediates different effects in mESCs depending on its receptor dosage, opening perspectives for balancing self-renewal and lineage commitment.

Background There are limited data to detail the perioperative anesthetic management and the incidence of postoperative respiratory complications among patients requiring an anesthetic procedure while being SARS-CoV-2 positive or suspected. Methods An observational multicenter cohort study was performed including consecutive patients who were SARS-CoV-2 confirmed or suspected and who underwent scheduled and emergency anesthesia between March 17 and May 26, 2020. Results A total of 187 patients underwent anesthesia with SARS-CoV-2 confirmed or suspected, with ultimately 135 (72.2%) patients positive and 52 (27.8%) negative. The median SOFA score was 2 [0; 5], and the median ARISCAT score was 49 [36; 67]. The major respiratory complications rate was 48.7% (n = 91) with 40.4% (n = 21) and 51.9% (n = 70) in the SARS-CoV-2–negative and –positive groups, respectively (p = 0.21). Among both positive and negative groups, patients with a high ARISCAT risk score (> 44) had a higher risk of presenting major respiratory complications (p p = 0.1, respectively). Discussion When comparing SARS-COV-2–positive and –negative patients, no significant difference was found regarding the rate of postoperative complications, while baseline characteristics strongly impact these outcomes. This finding suggests that patients should be scheduled for anesthetic procedures based on their overall risk of postoperative complication, and not just based on their SARS-CoV-2 status.

International audience; Fetal growth restriction (FGR) the leading cause of perinatal mortality and morbidity is highly related to abnormal placental development, and placentas from FGR pregnancies are often characterized by increased inflammation. However, the mechanisms of FGR-associated inflammation are far from being understood. NLRP7, a member of a family of receptors involved in the innate immune responses, has been shown to be associated with gestational trophoblastic diseases. Here, we characterized the expression and the functional role of NLRP7 in the placenta and investigated its involvement in the pathogenesis of FGR. We used primary trophoblasts and placental explants that were collected during early pregnancy, and established trophoblast-derived cell lines, human placental villi, and serum samples from early pregnancy (n = 38) and from FGR (n = 40) and age-matched controls (n = 32). Our results show that NLRP7 (i) is predominantly expressed in the trophoblasts during the hypoxic period of placental development and its expression is upregulated by hypoxia and (ii) increases trophoblast proliferation ([3H]-thymidine) and controls the precocious differentiation of trophoblasts towards syncytium (syncytin 1 and 2 and β-hCG production and xCELLigence analysis) and towards invasive extravillous trophoblast (2D and 3D cultures). We have also demonstrated that NLRP7 inflammasome activation in trophoblast cells increases IL-1β, but not IL-18 secretion. In relation to the FGR, we demonstrated that major components of NLRP7 inflammasome machinery are increased and that IL-1β but not IL-18 circulating levels are increased in FGR. Altogether, our results identified NLRP7 as a critical placental factor and provided evidence for its deregulation in FGR. NLRP7 inflammasome is abundantly expressed by trophoblast cells. It is regulated by a key parameter of placental development, hypoxia. It controls trophoblast proliferation, migration, and invasion and exhibits anti-apoptotic role. NLRP7 machinery is deregulated in FGR pregnancies.

Background Hybridization of plants that differ in number of chromosome sets (ploidy) frequently causes endosperm failure and seed arrest, a phenomenon referred to as triploid block. In Arabidopsis, loss of function of NRPD1, encoding the largest subunit of the plant-specific RNA polymerase IV (Pol IV), can suppress the triploid block. Pol IV generates short RNAs required to guide de novo methylation in the RNA-directed DNA methylation (RdDM) pathway. Recent work suggests that suppression of the triploid block by mutants in RdDM components differs, depending on whether the diploid pollen is derived from tetraploid plants or from the omission in second division 1 (osd1) mutant. This study aims to understand this difference. Results In this study, we find that the ability of mutants in the RdDM pathway to suppress the triploid block depends on their degree of inbreeding. While first homozygous generation mutants in RdDM components NRPD1, RDR2, NRPE1, and DRM2 have weak or no ability to rescue the triploid block, they are able to suppress the triploid block with successive generations of inbreeding. Inbreeding of nrpd1 was connected with a transgenerational loss of non-CG DNA methylation on sites jointly regulated by CHROMOMETHYLASES 2 and 3. Conclusions Our data reveal that loss of RdDM function differs in its effect in early and late generations, which has important implications when interpreting the effect of RdDM mutants.

Despite a large body of evidence, the implementation of guidelines on hemodynamic optimization and goal-directed therapy remains limited in daily routine practice. To facilitate/accelerate this implementation, a panel of experts in the field proposes an approach based on six relevant questions/answers that are frequently mentioned by clinicians, using a critical appraisal of the literature and a modified Delphi process. The mean arterial pressure is a major determinant of organ perfusion, so that the authors unanimously recommend not to tolerate absolute values below 65 mmHg during surgery to reduce the risk of postoperative organ dysfunction. Despite well-identified limitations, the authors unanimously propose the use of dynamic indices to rationalize fluid therapy in a large number of patients undergoing non-cardiac surgery, pending the implementation of a “validity criteria checklist” before applying volume expansion. The authors recommend with a good agreement mini- or non-invasive stroke volume/cardiac output monitoring in moderate to high-risk surgical patients to optimize fluid therapy on an individual basis and avoid volume overload. The authors propose to use fluids and vasoconstrictors in combination to achieve optimal blood flow and maintain perfusion pressure above the thresholds considered at risk. Although purchase of disposable sensors and stand-alone monitors will result in additional costs, the authors unanimously acknowledge that there are data strongly suggesting this may be counterbalanced by a sustained reduction in postoperative morbidity and hospital lengths of stay. Beside existing guidelines, knowledge and explicit clinical reasoning tools followed by decision algorithms are mandatory to implement individualized hemodynamic optimization strategies and reduce postoperative morbidity and duration of hospital stay in high-risk surgical patients.

Background Idiopathic central precocious puberty (ICPP) is supposed to be non-existent in a context of testicular destruction that is typically present in Klinefelter syndrome (KS). Herein, we describe a rare case of ICPP in a Klinefelter patient (47,XXY) with 2 maternal X chromosomes. Moreover, we highlight the differences in gonadotropin levels in comparison to males with ICPP and a normal karyotype. Case presentation An 8 years old boy with a history of cryptorchidism was evaluated for precocious puberty (Tanner staging: P2/G3). Both testes measured 25x35mm. His hormonal profile confirmed a central origin of precocious puberty with high serum testosterone (4.3 ng/ml), luteinizing hormone [LH (3.5 UI/l)] and follicle stimulating hormone [FSH (7.7 UI/l)] levels. Luteinizing hormone-releasing hormone (LHRH) test amplified LH and FSH secretion to 24 and 14 UI/l respectively. Brain magnetic resonance imaging (MRI) was normal. No MKRN3 mutation was detected. He was treated for ICPP for two years. During puberty, he suffered from hypergonadotropic hypogonadism leading to the diagnosis of KS (47,XXY karyotype). Chromosomal analysis by fluorescent multiplex polymerase chain reaction (PCR) using X chromosome microsatellite markers identified 2 maternal X chromosomes. Analysing 8 cases of KS developing ICPP (our reported case and 7 other published cases) revealed that these KS patients with ICPP have higher LH and FSH levels during ICPP episode than in ICPP patients with a normal karyotype (ICPP with KS vs ICPP with a normal karyotype: LH levels 9.4 ± 12 vs 1.1 ± 0.6 UI/l; FSH levels 23.1 ± 38.5 vs 2.7 ± 1.5 UI/l). Furthermore, their response to gonadotropin-releasing hormone (GnRH) stimulation is characterized by excessive LH and FSH secretion (LH levels post-GnRH: 58 ± 48 vs 15.5 ± 0.8 UI/l; FSH levels post-GnRH: 49.1 ± 62.1 vs 5.7 ± 3.9 UI/l). Conclusions ICPP in boys is extremely rare. The pathophysiology of ICPP in KS is unknown. However, maternal X supplementary chromosome and early testicular destruction may play a significant role in the initiation of ICPP, in part explaining the relative “overrepresentation of ICPP in KS. Thus, karyotype analysis could be considered for boys suffering from ICPP, especially if testicular size is smaller or gonadotropins are significantly elevated.

The Sperm Chromatin Structure Assay (SCSA®), in addition to identifying the DNA Fragmentation Index (DFI) also identifies High DNA satiability (HDS), supposed to reflect the nuclear compaction of spermatozoa. However, data on what exactly this parameter reveals, its relevance and usefulness are contradictory. In order to shed light on this situation, spermatozoa of a cohort (HDS does not appear to be a reliable indicator of nuclear immaturity because it shows a weak correlation with the CMA3, AB and TB stains. The low correlation of HDS with sperm DNA fragmentation (TUNEL and SCSA®) and DNA condensation (CMA3, AB and TB) tests suggests that these two parameters could be decoupled. Unlike DFI and TUNEL, HDS has not been shown to correlate with classic clinical situations of male infertility (asthenozoospermia, teratozoospermia or astheno-teratozoospermia).HDS correlates poorly with most tests that focus specifically on the level of maturity of the sperm nucleus. To our knowledge, this study is the first to compare SCSA®, TUNEL, AB, TB and CMA3 assays on identical samples. It shows the potency, consistency and limitations of each test and the care that must be taken in their interpretation.Le test SCSA® (Sperm Chromatin Structure Assay), en plus d’identifier l’indice de fragmentation de l’ADN (DFI = DNA fragmentation Index), identifie également la susceptibilté à la coloration à l’acridine orange de l’ADN (HDS: High DNA Stainability), censée refléter la compaction nucléaire des spermatozoïdes. Cependant, les données sur ce que révèle exactement ce paramètre, sa pertinence et son utilité sont contradictoires. Afin de faire la lumière sur cette situation, les spermatozoïdes d’une cohorte (Le HDS ne semble pas être un indicateur fiable de l’intégrité nucléaire car il montre une faible corrélation avec les tests CMA3, AB et TB. La faible corrélation du HDS avec les tests de fragmentation de l’ADN du sperme (TUNEL et SCSA®) et de condensation de l’ADN (CMA3, AB et TB) suggère que ces deux paramètres pourraient être découplés. Contrairement au DFI et au TUNEL, il n’a pas été démontré que le HDS est. corrélé avec les situations cliniques classiques de l’infertilité masculine (asthénozoospermie, tératozoospermie ou asthéno-tératozoospermie).Le HDS présente une faible corrélation avec la plupart des tests qui se concentrent spécifiquement sur le niveau de maturité du noyau du sperme. À notre connaissance, cette étude est. la première à comparer les tests SCSA®, TUNEL, AB, TB et CMA3 sur des échantillons identiques. Elle montre la puissance, la cohérence et les limites de chaque test et le soin qui doit être apporté à leur interprétation.

Testes produce spermatozoa that transit through and are stored in the epididymis where they acquire their fertilising capacities. Spermatozoa appear in the genital tract at puberty, long after the immune system was trained to self-antigens. As a consequence, this organ has to set strategies to tolerate sperm antigens to avoid autoimmune responses that would specifically target and destroy them. A recent study pointed the Transforming Growth Factor-beta (TGF-β) signalling in the dendritic cells as a crucial mechanism for epididymal tolerance to spermatozoa. In the mouse, TGF-β exists under three isoforms, and three distinct receptors have been described. Using RT-qPCR, immunohistochemistry and ELISA techniques, we investigated the expression and spatial distribution of the epididymal TGF-β isoforms and of their receptors in young and adult mice. We showed that both ligands and receptors were produced by immune and non-immune cells in the epididymis, whatever the age mice have. These data bring new clues as to the mechanisms of peripheral tolerance to sperm cells in the murine epididymis and raise potential other implications of the cytokine isoforms.

International audience; BACKGROUND:We investigated the association between antidepressant and anxiolytic exposure during the first and early second trimester of pregnancy (

International audience; Signal Transducer and Activator of Transcription 3 (STAT3) is aberrantly activated in glioblastoma and has been identified as a relevant therapeutic target in this disease and many other human cancers. After two decades of intensive research, there is not yet any approved STAT3-based glioma therapy. In addition to the canonical activation by tyrosine 705 phosphorylation, concordant reports described a potential therapeutic relevance of other post-translational modifications including mainly serine 727 phosphorylation. Such reports reinforce the need to refine the strategy of targeting STAT3 in each concerned disease. This review focuses on the role of serine 727 and tyrosine 705 phosphorylation of STAT3 in glioma. It explores their contribution to glial cell transformation and to the mechanisms that make glioma escape to both immune control and standard treatment.

Knowledge of integrative physiology is a major challenge for scientists, as even small deregulation could lead to diseases. Cells communicate with each other to control many processes such as growth, migration, survival, or differentiation. Such interaction could be achieved via several mechanisms either through cell-cell interactions and/or through the signaling of molecules that bind to receptors on the membrane or in the target cells. The produced molecules could have either autocrine, paracrine stimulations, or even act on distant organs (endocrine signaling).

Within the abstract, the following sentence: “Using the fully adjusted estimates of risks, active commuting decreased all-cause mortality by 9% (95% confidence intervals 3–9%), and cardiovascular mortality by 15% (3–27%) (p

International audience; Arylsulfatase A (ASA) is a lysosomal enzyme involved in the catabolism of cerebroside sulfate. ASA deficiency is associated with metachromatic leukodystrophy (MLD). Low ASA activities have also been reported in a more common condition with no apparent clinical consequences termed ASA pseudo-deficiency (ASA-PD) which is associated with two linked mutations in the ASA gene (c.1049A > G and c.*96A > G). This study aimed to investigate the frequency of the two ASA-PD variants and their linkage disequilibrium (LD) among Tunisians. ASA-PD variants were detected in 129 healthy Tunisians and their frequencies were compared to those described worldwide. The frequency of the PD allele was estimated at 17.4 % for the overall sample, with c.1049A > G and c.*96A > G frequencies of 25.6 and 17.4 %, respectively. This study also revealed a high LD between the two ASA-PD variants (r (2) = 0.61). Inter-population analysis revealed similarities in the ASA-PD genetic structure between Tunisians and populations from Middle East with c.*96A > G frequencies being the highest in the world. A significant North vs. South genetic differentiation in the ASA-PD frequency was also observed in Tunisian population who seems genetically intermediate between Africans, Middle-Easterners and Europeans. This is the first report on the allele frequency of the ASA-PD in North Africa, revealing a relatively high frequency of the PD allele among Tunisians. This study gives also evidence on the importance of discriminating ASA-PD allele from pathological mutations causing MLD and supporting enzymatic activity testing with both sulfatiduria determination and genetic testing in the differential diagnosis of MLD in the Tunisian population.

International audience

International audience; Small DNA tumour viruses have evolved a number of mechanisms to drive nondividing cells into S phase. Virally encoded oncoproteins such as adenovirus E1A and human papillomavirus (HPV) E7 can bind an array of cellular proteins to override proliferation arrest. The DNA methyltransferase Dnmt1 is the major mammalian enzyme responsible for maintaining CpG methylation patterns in the cell following replication. One of the hallmarks of tumour cells is disrupted DNA methylation patterns, highlighting the importance of the proper regulation of DNA methyltransferases in normal cell proliferation. Here, we show that adenovirus 5 E1A and HPV-16 E7 associate in vitro and in vivo with the DNA methyltransferase Dnmt1. Consistent with this interaction, we find that E1A and E7 can purify DNA methyltransferase activity from nuclear extracts. These associations are direct and mediated by the extreme N-terminus of E1A and the CR3 zinc-finger domain of E7. Furthermore, we find that a point mutant at leucine 20 of E1A, a residue known to be critical for its transformation functions, is unable to bind Dnmt1 and DNA methyltransferase activity. Finally, both E1A and E7 can stimulate the methyltransferase activity of Dnmt1 in vitro. Our results provide the first indication that viral oncoproteins bind and regulate Dnmt1 enzymatic activity. These observations open up the possibility that this association may be used to control cellular proliferation pathways and suggest a new mechanism by which small DNA tumour viruses can steer cells through the cell cycle.

International audience; The establishment and maintenance of epigenetic gene silencing is fundamental to cell determination and function. The essential epigenetic systems involved in heritable repression of gene activity are the Polycomb group (PcG) proteins and the DNA methylation systems. Here we show that the corresponding silencing pathways are mechanistically linked. We find that the PcG protein EZH2 (Enhancer of Zeste homolog 2) interacts-within the context of the Polycomb repressive complexes 2 and 3 (PRC2/3)-with DNA methyltransferases (DNMTs) and associates with DNMT activity in vivo. Chromatin immunoprecipitations indicate that binding of DNMTs to several EZH2-repressed genes depends on the presence of EZH2. Furthermore, we show by bisulphite genomic sequencing that EZH2 is required for DNA methylation of EZH2-target promoters. Our results suggest that EZH2 serves as a recruitment platform for DNA methyltransferases, thus highlighting a previously unrecognized direct connection between two key epigenetic repression systems.

International audience; In this review, we discuss recent advances in the knowledge of plant telomere maintenance, focusing on the model plant Arabidopsis thaliana and, in particular, on the roles of proteins involved in DNA repair and recombination. The question of the interrelationships between DNA repair and recombination pathways and proteins with telomere function and maintenance is of increasing interest and has been the subject of a number of recent reviews (Cech 2004, d'Adda di Fagagna et al. 2004, Hande 2004, Harrington 2004, Maser and DePinho 2004). Understanding of telomere biology, DNA repair and recombination in plants has rapidly progressed over the last decade, substantially due to genetic approaches in Arabidopsis, and we feel that this is an appropriate time to review current knowledge in this field. A number of recent reviews have dealt more generally with the subject of plant telomere structure and evolution (Riha et al. 2001, McKnight et al. 2002, Riha and Shippen 2003b, McKnight and Shippen 2004, Fajkus et al. 2005) and we thus focus specifically on plant telomere biology in the context of DNA repair and recombination in Arabidopsis.

Background Preeclampsia is a frequent complication of pregnancy and a leading cause of perinatal mortality. Both genetic and environmental risk factors have been identified. Lipid metabolism, particularly cholesterol metabolism, is associated with this disease. Liver X receptors alpha (NR1H3, also known as LXRalpha) and beta (NR1H2, also known as LXRbeta) play a key role in lipid metabolism. They belong to the nuclear receptor superfamily and are activated by cholesterol derivatives. They have been implicated in preeclampsia because they modulate trophoblast invasion and regulate the expression of the endoglin (CD105) gene, a marker of preeclampsia. The aim of this study was to investigate associations between the NR1H3 and NR1H2 genes and preeclampsia. Methods We assessed associations between single nucleotide polymorphisms of NR1H3 (rs2279238 and rs7120118) and NR1H2 (rs35463555 and rs2695121) and the disease in 155 individuals with preeclampsia and 305 controls. Genotypes were determined by high-resolution melting analysis. We then used a logistic regression model to analyze the different alleles and genotypes for those polymorphisms as a function of case/control status. Results We found no association between NR1H3 SNPs and the disease, but the NR1H2 polymorphism rs2695121 was found to be strongly associated with preeclampsia (genotype C/C: adjusted odds ratio, 2.05; 95% CI, 1.04-4.05; p = 0.039 and genotype T/C: adjusted odds ratio, 1.85; 95% CI, 1.01-3.42; p = 0.049). Conclusions This study provides the first evidence of an association between the NR1H2 gene and preeclampsia, adding to our understanding of the links between cholesterol metabolism and this disease.

Background Eukaryotic translation initiation factor 2B (eIF2B), a guanine nucleotide exchange factor (GEF) and a key regulator of translation initiation under normal and stress conditions, causes an autosomal recessive leukodystrophy of a wide clinical spectrum. EBV-immortalised lymphocytes (EIL) from eIF2B-mutated patients exhibit a decrease in eIF2B GEF activity. eIF2B-mutated primary fibroblasts have a hyper-induction of activating transcription factor 4 (ATF4) which is involved in the protective unfolded protein response (UPR), also known as the ER-stress response. We tested the hypothesis that EIL from eIF2B-mutated patients also exhibit a heightened ER-stress response. Methods We used thapsigargin as an ER-stress agent and looked at polysomal profiles, rate of protein synthesis, translational activation of ATF4, and transcriptional induction of stress-specific mRNAs (ATF4, CHOP, ASNS, GRP78) in normal and eIF2B-mutated EIL. We also compared the level of stress-specific mRNAs between EIL and primary lymphocytes (PL). Results Despite the low eIF2B GEF activity in the 12 eIF2B-mutated EIL cell lines tested (range 40-70% of normal), these cell lines did not differ from normal EIL in their ATF4-mediated ER-stress response. The absence of hyper-induction of ATF4-mediated ER-stress response in eIF2B-mutated EIL in contrast to primary fibroblasts is not related to their transformation by EBV. Indeed, PL exhibited a higher induction of the stress-specific mRNAs in comparison to EIL, but no hyper-induction of the UPR was noticed in the eIF2B-mutated cell lines in comparison to controls. Conclusions Taken together with work of others, our results demonstrate the absence of a major difference in ER-stress response between controls and eIF2B-mutated cells. Therefore, components of the ER-stress response cannot be used as discriminantory markers in eIF2B-related disorders.